Empty white sign for flags (7)

I believe the answer is:

wearies

'flags' is the definition.

'empty white sign' is the wordplay.
'empty' says to hollow out the word (remove centre letters).
'sign' becomes 'aries' (star sign).
'white' with its middle taken out is 'we'.
'we'+'aries'='WEARIES'

'for' acts as a link.

I've seen this clue in The Guardian.

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